Engraving machine



July 27, .1948.

Filed April 1, 1946 L. BENTZMAN- ENGRAVING MACHINE 3 Sheets-Sheet 1 INVENTUR. low: Bhvrz/ mu BY M ABwMZ.

ATTORNEY July 27, 1948. L. BENTZMAN ENGRAVING MACHINE 5 Sheets-Sheet 2 Filed April 1, 1946 U ml? n. M VZAO N T [N T E A P 0 L W g F July 27, 1948; BENTZMAN 2,445,903

ENGRAVING' MACHINE Filed April 1, 1946 3 Sheets-Sheet 3 m INVQVTOR.

ATTORNEY Patented July 27, 1948 ENGRAVI'NG MACHINE I lioui's Bentzman... New York, N. Y.,, assignorto Accmatool' 00., Inc., New York,

poration;

N. Y., a con- Application April 1, 1946,, Serial No. 658,675

5.- Claims. (01. 90-452.)

1 This invention relates toengraving machines, and; more particularly, though not exclusively, to machines having an engraving tool which cuts into a surface-oi an article in order to reproduce thereon any desired characters or design from a pattern.

In machine's of this typ the tracing movement of a stylus on a pattern to be reproduced is transmitted to the tool holder, and the latter is usually depressible. independently of its tracin movement in order to enable an operator to bring the engraving tool into cutting engagement with different articles of various sizes and shapes and to regulate the depth of the cut. Since even slight variation in the depth of the engraving results in an unsightly appearance of the same, and may even spoil the engraved article, the depth of the cut must be uniform throughout the engraving. Hence, the operator endeavors to depress the tool holder uniformly during the engraving operation. This is a very difiicult task and requires considerable skill and patience on the part of the operator, considering that he not only has to pay utmost attention to the depth regulation of thecut in the article, but has to trace the pattern with thestylus at the same time. The task of depressing the tool holder uniformly during an engraving operation on an article is even more formidable when the engraving tool has to be raised from, and returned into contact with, the article a number of times to complete the engrating, and is particularly formidable when the surface to be engraved of an article is. curved in one or more directions.

It is the primary object of the present invention to make provision in a machine of the above type for positively stopping the depression of the tool holder, through contact with the surface to be engraved of an article, when the engraving tool cuts to a required depth into said urface at any place thereon, thereby relieving the operator of. the burden of attaining uniform depression of the tool holder during an engraving operation, and assuring that no portion of an. engraving is cut deeper than required.

It is a further object of? the present invention to make provision for positively stopping the. depression of the tool holder when. the engraving tool cuts: to a required depth anywhere in a surface to be engraved of an article, regardless of whether the surface is plane or curved in one or more directions, or both. 7

The above and other objects of the present invention will be apparent from the following de scription taken in connection with the accompanying drawings, in which:

Fig. 1 is a perspective view of'an engraving ma.- chine embodying the presentinventiom Fig. 2 is an enlarged, fragmentary vertical section through the cutter head of the machine; in.- cluding the tool holder.

Fig. 3 is an elevational view, partly in. section, of the tool holder and parts carriedthereby;

Fig. 4 is a plan: view of the tool hold-eras viewed in the direction of the. arrow 4' in Fig- 3,. certain parts. thereof being shown partly broken away for better illustration of otherparts rtherebelow.

Fig. 5 is a section taken on the line 5-5. of Fig; 4.

'Fig. 6 is a section taken. on the line 6& of. Fig. 3.

Fig. 7 shows the tool holder and the parts. car:- ried thereby in a position of operation diflerent from that shown in Fig. 2.

Fig. 8 is a section taken on the line 8'8r of Fig. 3.

Referring to the drawingspandparticularly to Fig. 1 thereof, the reference: numeral l0 desige hates an engraving machine of the type referred. to, which may be supported on a table or bench l2; The engraving machine; comprises. a housing. It: which is suitably mounted on: the bed H5. or the machine for'movement. in any direction in the plane of said bed. The machine is equipped with 'a stylus I 5 which is carried by the handle it which is fixed rigidly to housing I4, the stylus being used to trace a pattern to be reproduced. on an article ll and the handle l9 serving to transmit the. tracing movement of the stylus to the housing I 4.

Mounted for movement in vertical guidewa-ys i8 on the housing I4 is a cutter head. or bracket 20 which is normally urged by a spring 22- into an uppermost position in which a stop 24 on. said cutter head engages a shoulder 26 on the housing M. i The spring 22, which is: spirally wound in the present instance, is suitably anchored with one end on a stud 28 in the housing l4, and with the other end on a stud 3|! in the cutter head 2t. A handle 32 is carried by the cutter head 20' to depress the latter (Fig. l) 1 Mounted in a cylindrical recess 34' the cutter head 2!] is an electric motor 36 (Fig; 2), the shaft 38 of which is suitably coupled at 413 to a spindle 42, carrying a chuck 44 which holds an engravrent of volts, for instance, and has an. electric cord (not shown) which may beplugged into any 3 conventional wall socket. A manual switch 41 on the cutter head 26 serves to start and stop .the motor 36 when the electric cord is plugged in a socket. The spindle 42 is journalled in ball bearings 48 in a cylindrical extension 49 of a spindle housing 50 (Fig. 3) which is suitably secured in the lower end of the cylindrical recess 34 in the also Figs. 4 and 8), which are pivotally connected 6 at 16 with follower legs 63 on opposite sides of the collar 52. Each pivot connection between a follower ring 66 and a follower leg 68 is preferably of the type shown in Fig. 5, and comprises pivot screws I2 which are threaded into the adjacent forked end "of the follower ring and project with their conical ends 16 into correspondin'gly formed recesses 18 in the follower leg. Nuts 86 serve to lock the pivot screws 12.

The follower rings 66 and the portions of the follower legs 68 intermediate the pivots 10 form a parallelogram (Figs. 2, 3 and 7) of which. the sides 66 are pivoted midway of the parallelogram to the .collar 52 as at 64, so that the folllower legs 68 move equal amounts in opposite directions when either one of these legs 68 is moved in either direction. Moreover, the axes of the pivots 64 extend at right'angles to the longitudinal axis of the engraving tool 46, wherefore the follower legs 68 move longitudinally of the tool 46. The follower legs 68 are preferably shaped as shown in Figs. 2, 3 and 7, and extend with their ends 8| into close proximity to the cutting tip 82 of the engraving tool, The legs 68 preferably carry at their ends 8| follower feet or shoes 84 (see also Fig. 6) which are pivotally mounted thereonias at 86. The ends 8! of the follower legs 68 are equally spaced from the longitudinal axisx of the engraving tool 46 (Fig. 2), and their pivot connections 86 with the feet 84 are preferably in line with the tip 82 of the engraving tool.

In orderto engrave the article I'i (Fig. l) which. may be a flat metal plate, for instance, or which may be a curved plate, the operator preferably secures the article in a work clamp 30 on the bed It of the machine and starts the electric motor 36. The operator then depresses the cutter head 26 by the handle 32 to start the engraving operation. While the tool 46 actually engraves the article, the operator depresses the cutter head 20 so as to keep the follower feet 84 in contact with the surface being engraved (Figs. 1 and 2) thereby obtaining a uniform depth of cut through the engraving, as will be readily understood.

The present stop means 84, 68, 66 is ideally suited for engraving curved surfaces of articles, such as the article I l in Fig. 7, for instance, since therfeet 84 follow the contour of the curved surface without permitting any variation in the depth of the cut therein by the engraving tool. This holds true even when the surface to be engraved of an article is curved in more than one direction. Thus, convex or concave surfaces may be engraved most uniformly in the present machine. The instant stop means is also of ad- 4 vantage in engraving surfaces of many other contours too numerous to describe, in that it controls the depth of the out throughout an engraving in a surface of most any contour, with the result that the engraving appears most uniform to the eye.

In order to vary the depth of the cut of the engraving tool in a surface, the stop means 64, 68, 66 is made adjustable longitudinally of the engraving tool 46. To this end, an externally threaded portion 93 of the collar 52 is in threaded engagement with an adjustment nut 92 (Fig. 3) which normally bears against the web 54 of the T spindle housing 56L On turning the adjustment of the spindle housing (Fig. 3), as will be readily understood. 1

Iclaim: 1. In an engraving'machine, the combination of a holder, an engraving tool having a cutting: tip and being mounted'for rotation about its longitudinal axis in said holder, two stop members on opposite sides of the cutting tip of said tool equally spaced from the longitudinal axis of the latter, and means carried 'by said holder for supporting said members for movement longitudinally of said tool andfor drivingly connectingsaid members so that they move equal amounts in opposite directions on moving either member in either direction, said members being adapted to contact a surface to be engraved of an'article when the tip of the rotatingtool cuts into said surface to a predetermined depth.

2. The combination in an engraving 'machineas set forth in claim 1, in which said means is mounted on said holder for adjustment longitudinally of said tool to vary the depth of the cut of said tool in said surface.

3. In an engraving machine, the combination of a holder, an engraving tool having a cutting tip and being mounted for rotation about; its longitudinal axis in said holder, and four arms pivotally connected to form the sides of a parallelogram of which two opposite arms are pivoted to said holder midway of said parallelogram about parallel axes at right angles to the longitudinal axis of said tool, and the other arms have stop surfaces on opposite sides of the cut ting tip of said tool equally spaced from the longitudinal axis of the latter, said stop surfaces being adapted to contact a surface to be en graved of an article when the tip of the rotating tool cuts into said surface to a predetermined depth.

4. The combination in an engraving machine as set forth in claim 3, further comprising contact shoes pivoted tosaid other arms and providing said stop surfaces. c

5. The combination in an engraving machine as set forth in claim 3, in which said holder com prises a cylindrical member which has a sh'oulder and in which said. tool is rotatably mounted; an element, axially slidably on said member longitudinally of said tool andnormally yield'-: ingly urged toward said shoulder, said element having a threaded portion and pivotally carrying said opposite arms, and a nut in threaded en- 6 gagement with the threaded portion of said element and interposed between the latter and said UNITED STATES PATENTS V shoulder. Number Name Date v 1,696,032 Glover Dec. 18, 1928 LOUIS BENTZMAN' 5 1,705,957 Braren Mar. 19, 1929 REFERENCES CITED FOREIGN PATENTS The following references are of record in the Number Country Date file of this patent: 387,512 Germany Jan, 5, 1924 

